You need to enable the SPI in config.txt and reboot, it is under the boot folder but the folder have slightly different names to a std Raspbian OS.
If the 7c80 is similar to the 7c81 the spi pins are hardwired to the first spi port on the first spi interface.
linuxcnc.org/docs/html/man/man9/hm2_rpspi.9.html
The hm2_spix is pretty much the same. As you can see from the above the SPI signals are hardwired.
If the SPI circuit of the 7c80 is based on the 7c81 design:
Basically without creating a custom cable (which I mentioned previously) the only SPI interface is using the following pins
MOSI=10(19), MISO=9(21), SCLK=11(23), CE0=8(24)
To tell the truth I'm not even sure spidev10.0 is for end user use. I think the only pins exposed on the 40 pin header are for spidev1.xx & spidev0.xx
The reason the card will be seen when using halcmd is that the hm2_spix driver takes full control of the hardware regarding the spi pins. To put it simply it replaces the kernel module that handles spi hardware.
Summarizing:
Mesaflash requires the devnodes for spi to be created by the kernel. Which physically limited to /dev/spidev0.0
hm2_rpspi & hm2_spix don't use the dev nodes as the setup for the GPIO is done by the Linuxcnc driver. Yet phsycially physically limited to the GPIOS associated with /dev/spidev0.0
Without specifying a spi interface it will default to the hardware (GPIO pins) associated with /dev/spidev0.0
An alternate interface can be specified but the physical connections between the RPi and the Mesa board need to be changed to suit. ie CS, CLK,MISO& MOSI will be the same at the mesa end but will need changing at the RPi end.
